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LABELING GELS
If you run a gel of any kind, always take a picture of it and label that picture, even if it did not work out and must be repeated. ALWAYS. Always email that labeled picture to your mentor the same day you run the gel. Do not run a gel with plans to label it later, or to email it later. Always label and email a picture the day the gel was run. Labeling gels very thoroughly is one of the most important favors present you can do for future you, and it's also one of the biggest courtesies you can do for someone who is helping you to interpret a gel. Leaving out all of the correct labels on a gel before you stick it in your notebook is almost as bad as leaving out the necessary controls from an experiment: in a few days, when some details are not immediately in your mind any longer, it will be essentially impossible to interpret that gel, or at best possible only through painstakingly cross-referencing what you did. Again, the most likely beneficiary of correct labeling is you, a week or a month from now, so please do future you a favor. For all DNA gels of PCR reactions, in every single lane, it should be clear what the template was, and what the primers were. TEMPLATE LABELS: ''' For the template, this should be the actual MM# for the yeast strain, bacterial strain, plasmid or miniprep, or worm strain, from our dropbox folder spreadsheets, if one of these four types of things was the template. For tetrads, you should make it clear what the expected genotypes for this single locus are, since other loci will be covered in different lanes using different primers typically. For tetrads it should be noted which lanes exhibited growth on which related markers. ASIDE: If it is one of these four types of things, and it is not in the dropbox folder spreadsheets already, stop what you're doing and completely fill out a row in the appropriate dropbox folder spreadsheet (and label a numbered tube in the -20 or -80 to store this template in the correct box) before proceeding any further. In addition to the MM#, you can add something short and descriptive, e.g. the genotype, or plasmid abbreviation. TEMPLATE LABEL EXAMPLE: MM1354 hap4::KanMX TETRAD LANE TEMPLATE EXAMPLE: ubp8D G418+ (or say UBP8WT G418-) '''PRIMER LABELS: For the primers, again this label should contain at a minimum the MM# from our primer spreadsheet in the dropbox folder, which is also in the oligo datasheet binders. ASIDE: If your primers do not have an MM#, stop what you're doing and fill out a complete row for each primer in the spreadsheet, and number and label the tops of the tubes and store the primers in the appropriately numbered primer box in the -20. Be sure that your predicted band size(s), as appropriate, are always included in the spreadsheet. ALSO include the sheets that the vendor sends with the primers, in the current volume of the "Oligo Datasheets" binder, and sharpie on the MM#, dillution information and concentration, and the predicted band size(s) on these sheets. If you used a web based tool or something that doesn't save a copy of your work to generate the primers, print out a copy of the design work and stick it in the primer design section of the binder. In addition to the MM numbers of both primers (you can shorten e.g. MM519 and MM520 to MM519/20 in a pinch), you can write something short and descriptive if you like, and if it will fit, but always have the MM numbers. PRIMER LABEL EXAMPLE: MM672/73 RPL22A (here I would put RPL22A underneath MM672/3 probably). 'EXPECTED BAND SIZE INFORMATION: '''Somewhere in the margins of the gel picture, you should make it clear what band size these specific primer pairs are predicted to produce, for each primer pair. If a primer pair is being used to distinguish two possibilities, e.g. for genotyping, then the two possibilities, and the sizes for BOTH of these possibilities should be listed. EXPECTED BAND SIZE EXAMPLE: For the primers used in the example above, then below the gel you'd say something like: "MM672 / MM673: RPL22A 1132bp, rpl22a::KanMX 1600bp". '''LADDER BAND SIZES: '''Although we all are used to looking at the same brand of hyperladder DNA ladder, there are many ladders (and even many different hyperladders) out there, including in use right in our lab, so labeling your ladder sizes is important. '''INTERPRETATION: ' If you already know your conclusions / interpretations from the results of the gel when you first label it, you can add them below immediately. If it's not clear or you are learning, you can go back and type these in and reprint your gel once you understand clearly what the gel means. Always add the interpretation in a way the is unequivocal once you understand it. EXAMPLE INTERPRETATION: Bands 2 and three show the rpl22a::KanMX deletion while band four shows RPL22A wild type. Freeze down strains used as templates for bands 2 and 3, as strains MM2834 and MM2835. EXAMPLE INTERPRETATION: No bands present except in wild-type control template. Re-check growth on G418 plates and re-run PCR in 2 days after growth is verified. Review / confirm primer sequences for MM672 and MMM673 in UGENE today.